Problem with texture applying
Looking at your screenshot, I can see that it is a generated image. It is blank, which is why it is black. When adding a new image from the UV/image editor, choose an option other than blank, (color grid or uv grid) if you want to use a default image from within Blender. 



You do need to save the image that you create as well if you use a generated image. You will notice an asterisk next to image in the editor header if the image has not been saved as it is in your screenshot.